more helpful error to catch symbolic shape vecs in infer_shape

Add warning for bug in Numpy <= 1.6.1.

When using numpy's advanced indexing on huge arrays (2**32 elements or
more), Numpy <= 1.6.1 has a bug where the resulting array is not
properly filled. We emit a warning in those cases.

Use C code for Alloc of broadcasted scalar

Fix blas tests

C code for integer division

Minor stuff

Thanks Olivier :) Is great to have someone like you involved in the project, that is able to notice and fix all the small details. 

additions and improvements to blas on both CPU and GPU (including GEMV, GER in blas_c)

Remaining scan errors

We should use optimization tags to enable, disable them. This also could cause problem on test in case there is a bug, teardown would not be executed per James comments.

It seems that even the last fix of the generated random numbers didn't do
the trick. The reason being same numeric instability.
I've change the operation to a sum, which, if you apply it recursevly is
less problematic then multiplying numbers

Fixed crash at exit time if cache was deleted

Fixed some tests broken due to exception verbosity

Also use textwrap.dedent to avoid adding indentation to the final C
code.